Apparatus for making glued corrugated cartons



Dec. 23, 1958 c. A. STRAND 2,865,263

APPARATUS FOR MAKING GLUED CORRUGATED CARTONS Filed Sept. 28, 1956 2 Sheets-Sheet 1 INVENTOR. GIJFFORDA. STRAND "72 mm i-PWM ATTORNE YS Dec. 23, 1958 c. A. STRAND 2,365,263

APPARATUS FOR MAKING GLUED CORRUGATED CARTON-S Filed Sept. 28, 1956 2 Sheets-Sheet 2 46 95 2 I 45* II-46 INVENTOR.

lm nu u" I" ATTORNEY S 2,865,263 APPARATUS son MAKING GLUED CORRUGATED CARTONS liflord A. Strand, Nashua, H., assignor to The International Paper Box Machine Company. Nashua N. H., a corporation of New Hampshire Applicationseptember 28, 1956, Serial N: 612 ,729" 3 Claims; (or. 93-41) This invention relates to an apparatus for. squaring up and levelling the edges of glued tray boxes of c'o'rrugated paperboard formed on plunger and channel type box forming machmes.

Plunger and channel type box forming machines are well known and are often used to make box trays of the glue flap or lock flap type. The plunger or box form of such machines forces a fiat blank into the box fortning channel to cause the side walls to erect" and the attachment flaps to infold along the side walls in tray form. When lock flaps are" used and when the material is ordiriary paperboard or the like, the r'esultinglt'ray is somewhat flexible and if the flaps fail to entirely interlock a light tap, or light pressure on the outer edges will complete the flap engagement.

With glue flap type box trays, however, it will be understood that if the glue flaps are adhered to the sidewalls when the box is not squared up, or the edges are not levelled, such condition is permanent and the box is usually not acceptable in the trade. When the material is of corrugated paperboard, there is an increased likelihood of defective glue flap type box trays for the reason that the flutes of the board may be misaligned and cause misfolding on the lines of fold, the board presents much greater resistance to folding and the boxes are usually much larger than normal whereby any warp, or anyprotruding glue flap edge, is correspondingly increased and more noticeable.

The principal object of this invention is to provide an apparatus whereby glued box trays of corrugated paperboard, and of various sizes, may be automatically and positively trued up and leveled just prior to the app'lic'a tion of glueing pressure and thereby assured of forming a perfect box tray.

Another object of the invention is to provide apparatus in a plunger and channel type box forming machine for glue flap boxes in which the glue flaps are leveled with the side walls by individually adjustable means Spaced entirely around the plunger mechanism and requiring no complicated or weighty actuating mechanism.

A further object of the invention is to provide low cost, simple apparatus on a box forming machine for producing glued box tray of corrugated material in which the glue flaps are levelled with the side walls even if the flaps are initially folded on misaligned fold lines.

Other objects and advantages of the apparatus of the invention will be apparent from the claims, the description of the drawing and the drawing in which a preferred embodiment of the invention is illustrated.

Fig. 1 is a somewhat diagrammatic side elevation, partly in section of a portion of a plunger and channel type box forming machine with the apparatus of this invention installed thereon.

Figs. 2, 4, 6, 8 and 10 are front elevations of the squaring up and levelling mechanism of the invention in the various stages of forming a box tray from a flat blank.

Figs. 3, 5, 7, 9 and 11 are side elevations, corresponding to said front elevations of the invention.

uited States Patent 2,865,263 Patented Dec. 23, 1958 ice 12 is a bottom view of a typical blank of the' type to be. folded and glued into a squared up, levelled edge box tray by the device of this invention. p

In Fig. 1 a portion of a machine 20 is" illustrated, sufficient to show the invention hereof, the remaining parts of the machine being well known; The machine 20 includes a frame 21 having an endless conveyor 22 and an accelerating roll 19 for feedingv flat blanks in the direction of the arrows totheentrance 23 or the box forming channel 24. The flat blanks such as 25 are fed inf dividually and successively to the channel entrance 23 and into the path of theplunge'r2'6 as illustrated in Figs. 2 21.1.1431

Each blank such as; 25' is of a well known typeh'avi-ng a bottom- 28, four side walls 29, 30, 31 and 32', and a pair of oppositely disposed glue flaps 33, 34 and 35, 3 6 hingedly connected along flap fold' lines 37 and 38 toa pair ofopposite side walls such as 30 and 32. The blanks 25 are formed of corrugated paperboard and the flutes thereof may tend to cause misfolding because the flutes are slightly misaligned or because of the resistance to folding of the fluted st'ru'cturep Eachblank 25 forms a tray box 40, shown in Figs. 10- and ll, of the glue flap type and while the box may be acceptable in the trade it it is not perfectly squared up, it is not. acceptable if the glue flaps such as 34 and 36 project beyond the adjac'ent side wall such as 29 in the condition shown in Fig. 7. It is, of course, most desirable that the free outer edges such as 41 and 42 of the glue flaps 3'4 and 36 be flush with, and level with; the free' outer edge'sueh as 39 of the adjacent side wall 31 when the flaps are adhered thereto and that the tray box 40 be squared up during such adherence in order to permanently retainv a true and commercially acceptable shape.

The box forming channel 24 includes spaced elements such as 43 and 44 in the path of each glue flap33, 3'4, 35 and 36 and arranged to erect (or infold) the glue fl-aps as the plunger 26 forces the box bottom 28- through the channel. The side walls 30 and 32 engage the folding elements 45 and 46' to erect (or infold the same with their glue flaps and thereafter the side walls 29 and 31 are erected (or infolded) by engagement with pressure plates 50 and 51, outside the glue flaps. The elements such as 43 and 4-4 are mounted on the adjacent elements such as 45 and 46 and the latter are carried by brackets such as 52 and 53 supported on transverse rods 54 and 55. The rods 54 and 55 are supported onspaced frame pieces such as 56 extending above the blank path formed by the upper stretch of conveyor 22. Resiliently mounted catches such as at 57 are arranged for movement out of the path of a box 40 being formed in the channel and to then move back into said path to prevent the retraction of the completed box with the return portion of the plunger stroke. The catches 58 are mounted on bars such as 59', 60 depending from a member 61' carried by the square rod 62.

The rod 62 is vertically movable in timed relation to the other moving parts of the machine in a well known manner, by means of the slide rod 64 and guide 70 to lift each successive box upwardly into the stack and away from the channel 24. v

The plunger 26 includes a flat plate 65 slightly smaller in area than the area of a box bottom 28 and mounted at the terminal upper end of an actuating rod 66. Rod 66 is telescopably mounted within an actuating rod 67 for axial sliding movement and rod 67 is mounted for axial sliding movement within brackets 68 and 69 carried on machine 20. Rod 67 carries a box form 71 at its upper terminal end arranged to support the erected side walls 29, 3t), 31 and 32 of each successive box at a position normal to bottom 28 and also to support the erected aseaaas Walls 29 and 31 against the inward pressure of plates 50 and 51 during the adhesion of the glue flaps.

The rod 66 of plunger 26 is spring loaded downwardly by a spring 72 and positively moved upwardly by link 73, lever 74 rockably mounted on a shaft 75, cam follower 76 and cam 77 carried by shaft 78.

The rod 67 of box form 71 is also spring loaded downwardly by spring 79 and positively moved upwardly by link 80, lever 81 rockably mountedon a shaft 82, cam follower 83 and cam 84 carried by shaft 78.

The squaring up and levelling mechanism of this invention includes first lateral extensions such as 86 and 87 on the box form 71 and aligned with the outer edges such as 41 and 42 of the glue flaps 33, 34, 35 and 36 when erected and in position for adhesion. Preferably the first lateral extensions such as 86 and 87 are equal in lateral dimension to the thickness of a side wall and an adjacent glue flap in order that they may engage an edge 41 and an edge 39 simultaneously. In addition there are a plurality of spaced individually slidable lateral extensions such as at 88, similar to extensions 86 and 87, on the box form 71 and adapted to engage the free outer edges such as 89 of the walls 30 and 32 to assist in positively squaring up each tray box such as 40. As shown, the first lateral extensions 86, 87 and 88 are in the form of spaced lugs each having a slot 91 and fixed in place by a locking screw 92. An elongated, removable bar could be used for the purpose or an integral outwardly extending flange on the box form but the lugs illustrated do not add unnecessary weight and are individually adjustable to desired positions conforming to the blanks used.

The squaring up and levelling mechanism also includes second lateral extensions 94 and 95 on the pressure plates 50 and 51. The pressure plates 50 and 51, as shown in Figs. 2-5 are normally retracted laterally, in which posi-- tion they serve to infold the glue flaps. Upon erection of the flaps and walls of the blanks into the form of a tray box as in Figs. 6 and 7 the pressure plates move inwardly on their respective actuating rods 96 and 97, whereby the second lateral extensions 94 and 95 form a barrier or limit stop for further axial movement of the box.

With the box bottom 28 firmly seated at each opposite side on the second lateral extensions 94 and 95, but before adhesion pressure is applied by plates 50 and 51. the box form 71 advances up to plate 65 of plunger 26. The first lateral extensions such as 86 and 87, on box form 71, are so positioned as to apply axial pressure on the free outer edges 41 and 42 of the glue flaps toward the box bottom 28 and level the said edges with the free outer edges 43 of the adjacent side wall. If the box is not squared up the extensions 86, 87 and 88 force the outer edges of the glue flaps and walls into a plane parallel to the flat plane of the second lateral extensions 94 and 95 to assure a perfect box.

The earns 77 and 84 are arranged to cause the plunger 26 to precede the box form 71 into the channel 24 with the plate 65 of plunger 26 pushing the box bottom 28 ahead and the channel causing the fiaps and walls to erect or infold. As the plunger 26 nears the end of the forward portion of its stroke the pressure plates 50 and 51 move inwardly laterally to cause the second lateral extensions 94 and 95 to firmly seat the box. The box form 71 which has been trailing the plate 65, then advances to the end of the forward portion of its stroke as shown in Figs. 8 and 9 to square up and level the box ready for adhesion. The pressure plates 50 and 51, which are synchronized with the conveyor 22 and shaft 78 in any convenient manner well known in the trade, then advance to the end of the forward portion of their stroke to firmly adhere the glue flaps 33, 34, 35 and 36 to the side walls 29 and 31 while the box is held squared and levelled.

Thereafter the pressure plates and 51 are retracted outwardly on the rearward portion of their stokes and the cam 84 causes box form 71 to retract away from the plate of plunger 26. Plate 65 remains in position until the box 40 has been stripped from form 71 and is then caused by cam 77 to trail the box form out of the channel 24.

The completed boxes 40 are held in place in channel 24 by catch devices such as at 57 and 58 and each successive box formed pushes the preceding box further up into the stack, all in a well known manner.

I claim:

1. In plunger and channel apparatus for erecting tray boxes of the type having glue flaps, a box form, reciprocating axially along the path of said plunger in said channel, in timed relation thereto; a plurality of first, individual, slotted, lateral extensions spaced entirely around said box form, each fixed to said form by a locking screw in said slot and adapted to apply pressure on the edge of the erected walls and glue flaps of the box in a direction toward the box bottom for squaring up the box and leveling the flaps and adjacent walls thereof and oppositely disposed pressure plates reciprocating normal to the axis of said plunger and channel in timed relation thereto, said plates each having second lateral extensions fixed thereon adapted to limit the axial movement of said box and counter the pressure of said first lateral extensions, said first and second lateral extensions being adapted to maintain said box squared up and said flaps level during the application of adhering pressure by said pressure plates.

2. Apparatus for forming glued corrugated boxes, said apparatus comprising a box form reciprocating axially within said channel and arranged to support the erected side walls and glue flaps of a box from the inside thereof; a plunger telescopably mounted within said box form and arranged to erect the side walls and glue flaps of a box with each stroke thereof; timed means actuating said plunger and box form with said plunger preceding said form at a spaced distance into said channel and trailing said form at a spaced distance out of said channel; first lateral extensions fixed on said box form and arranged to apply pressure axially, toward the box bottom, on the outer edges of said erected side walls and glue flaps for squaring up the box and leveling the edges thereof; pressure plates, reciprocating laterally in timed relation to said plunger and form and arranged to apply lateral pressure inwardly on said erected, and box form supported, side Walls and glue flaps for adhering said flaps to said walls and second lateral extensions fixed to said pressure plates, said extensions being adapted to counter the pressure of said first lateral extensions and to cooperate therewith in maintaining said box in squared up condition with edges leveled during the application of pressure by said pressure plates.

3. A combination as specified in claim 2 wherein said timed means comprises separate cams, cam followers and rockable levers for actuating said plunger and box form and said cams are mounted on a single drive shaft for synchronizing the operation thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,563,184 Goss Nov. 24, 1925 

